Feeding glass.



No. 805,068. PATBNTED NOV. 21, 1905; H. K. HITOHGOGK.

FEEDING GLASS.

APPLICATION FILED JUNE 13, 1904.

2 SHEETSSHEET 1.

PATENTED NOV. 21, 1905.

H. K. HITGHCOOK.

FEEDINGGLASS.

APPLIGATION FILED JUNE 13, 1904.

2 SHEETS-SHEET 2.

w n u INVENTOR K.m.oc/K,

1 l i I i l I L UMA mum;

.UNITED STATES PATENT OFFICE.

HALBERT K. HITCHCOGK, OF WALTON, PENNSYLVANIA, ASSIGNOR TO HIMSELF ANDCHARLES W. BROWN, TRUSTEES, OF PITTSBURG, PENN- SYLVAN IA.

FEEDING GLASS.

Specification of Letters Patent.

Patented Nov. 21, 1905.

Application filed June 13, 1904:. Serial No. 212,355.

Be it known that I, HALBERT K. HITOHCOOK, a citizen of the UnitedStates, residing at lValton, in the county of Allegheny and State ofPennsylvania, have invented or discovered certain new and usefulImprovements in Feeding Glass, of which improvements the following is aspecification.

The invention described herein relates to certain improvements in thefeeding of glass from a tank, furnace, or otherv suitable reservoir tomolds or other shaping devices.

Molten glass resembles liquids in the manner of movement through andfrom an orifice t'. 6., it is dependent, with a given fluidity, upon thepressure on the supply-body and the size of the orifice. By suitablyregulating these the molten glass can be made to discharge drop by drop,and from a given orifice, with a given fluidity of glass, the quantityof glass in the drops can be varied within certain limits by varying thepressure on the supplyloody-i. 6., the greater the pressure the largerthe drops. By reason of the tenacity of the glass even when quite liquidthe drops will be connected with each other and with the supply-body bya thin thread, which will harden more quickly than the drops, and unlesssuch thread is severed before extending far from the supply-body andremelted it will be incorporated in such form in the next drop formed asto render the latter undesirable for use in the formation of an article.

The present invention has for its object a construction whereby it ispossible to eflect a step -by step, or, as it might properly be termed,a drop-by-drop, feed of the glass, each drop containing any desiredquantity of glass and to provide for the remelting of solid orpartially-solidified portions of glass formed in or adjacent to thedischarge-orifice between adjacent drops .or during any interruption ofthe feed of the glass from the tank or containing vessel.

The invention is hereinafter more fully described and claimed.

In the accompanying drawings, forming a part of this specification,Figure 1 is a side elevation of a portion of a furnace having myimproved feed mechanism applied thereto. Fig. 2 is a sectional elevationof the same. Fig. 3 is a top plan view showing a portion of the exhaustapparatus in section, and Fig. 4 is an end elevation.

In the practice of my invention my improvements are applied to anysuitable form of construction of tank, furnace 1, or other receptacle inwhich suflicient heat may be maintained to keep the glass in the desiredcondition of plasticity. From this tank or vessel extends a passage 2,communicating at exhaust device consists of a concave-convex metal shell6, to the edges of which is secured a flexible diaphragm 7. Thisdiaphragm is connected, preferably at its central point, to an arm 8,which-in turn is connected to one end of a lever 9, whereby to shift thediaphragm in and out, thereby creating and destroying a partial vacuumin the chamber 4: and the passages 2 and 3 connected thereto. As will bereadily understood by those skilled in the art, if while the glass isflowing freely through the passages 2 and 3 from the outlet thediaphragrn7 should be drawn suddenly outward a certain vacuum will beproduced, so that atmospheric pressure acting on the glass in thepassage 3 will force the glass backwardly into said passage and chamber4, the walls of which are heated by any suitable means.

A desirable construction for maintaining the passages 2 and 3 at atemperature at least equal to that of molten glass is clearly shown inFig. 2. The passages are lined with a highly-refractory material, ascarborundum, and this lining is surrounded by granulated carbon 6, whichis electrically connected to terminals 0 and they in turn to a suitablegenerator.

In feeding the glass into a mold or other receptacle suitable means areprovided whereby when a suflicient quantity has been placed in the moldthe glass between the dischargeorifice and the mold is severed and thedirection of movement of glass at the dischargeorifice may be reversed,so that the glass between the orifice and the shears at the time oftheir operation may be drawn back and its plasticity restored in thepassage. A suitable construction for severing the glass consists of twoshear-blades 10 and 10, one of which is secured to a shaft 11 and theother to a sleeve 12, surrounding the shaft. These blades are secured insuch angular relation to each other on the shaft and sleeve that whenrotating they will pass each other at diametrically opposite points, oneof the points corresponding to or lying in the axis of the passage 3,from which the glass exudes. The sleeve and shaft are rotating inopposite directions by any suitable meanssuch, for example, as thatshown, consisting of two beveled gears 13 and 13, mounted, respectively,on the sleeve and shaft and engaging a corresponding pinion 14 on acounter-shaft 15. This shaft is driven by vertical shaft 16 and it inturn by shaft 17 through suitable interposed gearing. As it is desiredthat the shear-blades should have a quick movement at the time ofsevering the glass, while at other times they may have a slowermovement, the shaft 17 is driven from the shaft 18 by means ofelliptical gearing 19, as shown.

When feeding the glass to molds where the latter are presented orbrought into line with the outlet from the furnace or chamber at regularpredetermined intervals, it is preferred that the operation of theexhaust mechanism should occur at similar equal predetermined intervalsand immediately subsequent upon the operation of the shear-blades. Tothis end a cam 20 on the power-shaft 18 is employed to operate the lever9. As the operation of the shear-blades is eflected from thepower-shaft, it follows that by a suitable adjustment of the mechanismsdescribed the shearing operation and the drawing up of the glass intothe feed-passage can be made to occur in any desired order and at anydesired time. The movement of the diaphragm can be regulated in anysuitable manneras, for example, by means of the screw 21, as shown inFig. 4.

The quantity of glass required to form any desired article having beendetermined, the pressure-regulating mechanism is adjusted so that thenormal pressure on the glass will cause the formation of drops orglobular bodies of the required size and at the desired rate just belowthe outlet from passage 3. The term globule as herein employed is notused to define any particular shape or configuration of the glass, butonly as defining a portion of glass which under the action of gravitywill separate itself from any other supported portion. The shape theglass assumes in the practice of my method is similar to that assumed byglass dropping from a punty in the usual glass gathering and feedingoperation. After each drop has been formed and fallen below the shearsthe latter operate to sever the thread connecting the drop and body ofglass. The portion of the thread connected to the drop will contracttoward the drop and be absorbed thereby, while the other portion ofthethread will be drawn by the operation of the exhaust mechanism into thepassage 3 and there remelted or prevented from solidifying. Theoperation of the shears should be so timed as to sever the thread asclose as possible to the supply-body.

It is characteristic in the operation described that if the diaphragmwere not to be operated the natural flow of glass would tend to form adrop as it exudes from the orifice 3, and if severed when formed theforce of cohesion will draw that part of the thread adhering to the mainbody up into the main portion or supply, thus forming the lower surfacefor the next drop, so that a series of drops will follow one another atgiven intervals dependent upon the various natural forces operatingthereon. If, however, the diaphragm 7 is operated at a time of severingthe drop to reduce the pressure in the chamber 4, the flow' of glassthrough passage 2 is accelerated and the glass at orifice 3 is drawncompletely up into the zone of heat, so that cooler portions are againreheated. Upon a reverse movement of the diaphragm, whereby pressure isincreased in chamber at, a rapid expulsion of the glass which hasaccumulated will occur, thereby causing the formation of a drop, largeor small, depending upon the rapidity of the movement of the diaphragmatthe orifice.

The invention described herein is not limited as regards the broad termsof the claims to any particular construction or arrangement ofmechanical devices whereby a vacuum higher or lower is applied to theglass flowing from the furnace so as to arrest such normal flow and topull back any glass which may have exuded from the discharge-outlet.

It is characteristic of the invention described herein that the feed ofthe glass can be controlledvl. e. decreased or reversedby varying theatmospheric pressure on the glass before it escapes from the outlet, andhence it is immaterial except as regards constructing and operating thecontrolling mechanism on what portion of the surface of the glass t'. e.within the tank or the passage leading therefrom-the pressure is varied.

I claim herein as my invention 1. As an improvement in the art offeeding glass to shaping mechanism, the method herein described, whichconsists in causing the glass to assume a globular form as it passesfrom the feed-orifice to the shaping mechanism and then detaching theglobule or drop from the supply-body, substantially as set forth.

2. As an improvement in the art of feeding glass, the method hereindescribed, which consists in causing the glass to assume a globular formof predetermined size or Weight, as it passes from the feed-orifice andthen detaching the globule or drop from the supply-body, substantiallyas set forth.

3. As an improvement in the art of feeding glass, the method'hereindescribed, which consists in causing the glass to assume a globularform' as it passes from the feed-orifice, and then reversing thedirection of movement of the glass at the orifice, substantially as setforth.

4. As an improvement in the art of feeding glass, the method hereindescribed which consists in causing a full flow of the glass through asuitable orifice and then checking such flow or feed movement of theglass by reducing the pressure on the glass at some point within theorifice below atmospheric pressure, substantially as set forth.

5. As an improvement in the art of feeding glass, the method hereindescribed which consists in causing the glass to flow through a suitableorifice'and then reversing the feed movement through such orifice byreducing 20 HALBERT K. HITOHCOOK.

Witnesses DARWIN S. WOLOOTT, F. E. GAITHER.

